AR57 is back

[BRZ]

Looks like Panzer Arms is now making the AR57. PSA has them listed on website.

[Toprudder]

New member here. I just picked up one of the Panzer uppers from PSA. My first 5.7x28 gun. Unfortunately, I discovered the chamber freebore is a little too short for the American Eagle 40 ammo, the bullets are jammed into the lands. I have some different ammo ordered that I will try out that will hopefully work.

One other issue I discovered is that a Magpul BAD lever installed on the bolt catch will not fit inside the recess milled into the upper. I had an existing upper with the BAD lever that I had intended to use, but I ended up building another stripped lower instead of removing the BAD lever.

I am also in the process of ordering the items I need to start Reloading this caliber.

[panzermk2]

Cool, welcome to the forum and thank you for the feed back. This is, I think, the fourth iteration of the AR57 .

[Toprudder]

Thanks. I got some FN and Speer ammo to try out, the bullets are not jammed into the lands, but none of the rounds allow the bolt to fully close. I made a chamber cast to see what was going on, and I believe the chamber isn’t reamed deep enough.

I have another email into Panzer, with photos, showing them everything. Oh, the first email I sent them, they told me that Federal ammo is terrible and not to use it, and to only use FN ammo.

[Toprudder]

Photo of chamber cast, showing amount of unsupported case:

https://imgur.com/gwtGzYl

Photo of bolt not fully closed.

https://imgur.com/FSzLD16

[panzermk2]

Damn that looks like the crap the second gen AR57's went through. ZERO quality control. Wonder if they had some NOS barrels sitting around, used them without checking them.

[Toprudder]

The email I got back from Panzer support said that was normal. I find it hard to believe.

[panzermk2]

Damn.

[skyrep]

Went out to test the AR57 with Federal 40gr rounds. Clocked the Federal 40gr at 1980 fps and sd's: 23.2 Fired approximately 40 round without any hick-ups. Was very pleased with how it shoots.

[Toprudder]

Went out to test the AR57 with Federal 40gr rounds. Clocked the Federal 40gr at 1980 fps and sd's: 23.2 Fired approximately 40 round without any hick-ups. Was very pleased with how it shoots.

Is this an original AR57 or one of the new Panzer AR57 uppers?

[skyrep]

It's the latest and greatest. Just got last month. Had an extra lower and built it up. Trigger Tech Trigger.

[panzermk2]

Another brand new owner of an AR57 in one of the FB groups is having this exact same problem of the rounds not chambering all the way.


I shared a link to this post with him


Just a heads up in case this turns into some sort of trend.

[Toprudder]

I went to the range today to test out my first handloads, and to test the heavy buffer.

I ran 10 rounds of factory Federal ammo with the stock buffer (4.8oz) and then with the heavy buffer (8.5oz). Both worked well, but I did have one light-strike, which is not the first time it has happened with the Federal ammo. I then tested the heavy buffer with 10 rounds each of Speer and FN ammo - no problems. Then I proceeded to try my test loads using the heavy buffer. All rounds (18 total) through the whole charge range fired and cycled fine.

I have considered getting a chamber reamer and reaming the chamber deeper so as to get the bolt to fully close, but I think I may keep it as it is now and just put more rounds through it. I also intend to keep the heavy buffer, I believe the slower cycling will help with reliability.

[Toprudder]

I took it out yesterday to shoot some more. Probably 70 rounds through it, flawless. I shot a combination of Federal AE and FN factory ammo.

[panzermk2]

So it's still behaving?

[Toprudder]

So it's still behaving?

It did that day. When I do have problems, it seems to be with the Federal AE ammo.

[panzermk2]

Well that ammo is known for being really bad.

[Duke_Landrunner]

I also picked up a Panzer Arms AR57. Found out that Panzer does not manufacture them. They are made by a small shop in the US, and marketed through Panzer USA. I've got 2 issues with mine: first, every round I've shot from it produces a "D" shaped opening on the casing (rather than the preferred "O"). The casing is being whacked against something during extraction or ejection. Reading multiple threads, that seems to be common. I only got one range session in before problem #2, but I ran FN, Federal AE, and Fiocchi through it, using an FN PS90 mag, the provided AR57 mag, and a PMag. Every single casing had the same damage. While shooting the 4th mag (of Fiocchi Hypervelocity 40 grain), one of the casings sheared off at the neck. Fouled the chamber. Surprise, with the mag-over-bolt design, I didn't know. Forensics (staring at the used brass) says I had 7 out-of-battery rounds that fired and bulged the casings. The 8th ruptured the casing and destroyed an FN magazine. Has anyone else heard of that little issue? I can't imagine how the dinged casings are related to the sheared neck ... but it seemed like an awful lot of bad luck all in one day.

[Armed Eye Doc]

I have an original AR57 and have the same D shaped case mouth.
I would suspect the case separation would be an ammo issue. Likely, the case was not weak for whatever reason. Maybe @panzermk2 can share his insight.

[panzermk2]

OK not an AR57 guy. I never really got into it. I have friends, hell one of them is a founding member of this forum and has dozens of videos, many I use, showing him shooting EA ammo through his first gen and it works perfect .


Denting of the case yes it's normal.

Your chamber, have you thoroughly cleaning with carb Cleaner on a 9mm patch bore brush. NO other cleaners touch the lacquer. It builds up causing not only extraction, but over pressure issues and case failures. The bolt design is NOT an issue when it comes to fouling. To be clear I said FOULING, not any other issue.

This has to do with chamber cleaning and while PS90 it applies to ALL fire arms that shoot the 5.7 https://youtu.be/3qaqnn-KFqY?si=rC0e6XJRmS5VzwlE

[panzermk2]

Shitty chamber cutting his the hallmark of Jarvis barrels, but I have also had feed back on AR57 chambers being out of spec or just really poorly reamed.

I would look into polishing the chamber, I would suggest using one of my/EA snap caps to test the but I haven't had those in stock since fucking covid.


More info her, and I also reached out to him for his input here as he would be the most knowledgeable person on the AR57 I know of.

https://youtu.be/8phcMfBFozE?si=ca9CTb1-Dsw4iU_t

[Gruntreviews]

These definitely need a heavy buffer to slow down bolt speed. Too light a buffer or spring can keep the bolt from full seating and can cause it to move too early during the firing cycle. QC was a huge issues with the AR57 units (gen 1-3) and the few I’ve handled of the Panzer (gen 4) seem to have corrected some of this. Magazine fitment is critical as well. Many of the gen1-3 units required the back of the mag to be shaved to seat fully. The gen 4 units seem to have corrected this issue with the ones I’ve handled.

[panzermk2]

And welcome to the forum!!!!!!!!!!!!!!

[Gruntreviews]

New member here. I just picked up one of the Panzer uppers from PSA. My first 5.7x28 gun. Unfortunately, I discovered the chamber freebore is a little too short for the American Eagle 40 ammo, the bullets are jammed into the lands. I have some different ammo ordered that I will try out that will hopefully work.

One other issue I discovered is that a Magpul BAD lever installed on the bolt catch will not fit inside the recess milled into the upper. I had an existing upper with the BAD lever that I had intended to use, but I ended up building another stripped lower instead of removing the BAD lever.

I am also in the process of ordering the items I need to start Reloading this caliber.

I’d recommend removing the bolt catch entirely, but I like to run the charging handle on the left side

[Duke_Landrunner]

Shitty chamber cutting his the hallmark of Jarvis barrels, but I have also had feed back on AR57 chambers being out of spec or just really poorly reamed.

I would look into polishing the chamber, I would suggest using one of my/EA snap caps to test the but I haven't had those in stock since fucking covid.


More info her, and I also reached out to him for his input here as he would be the most knowledgeable person on the AR57 I know of.

https://youtu.be/8phcMfBFozE?si=ca9CTb1-Dsw4iU_t

Thanks for all the info and videos! I had not cleaned the chamber for lacquer, but there were < 150 rounds through it when I experienced the case separation. I did not buy 5.7 gauges ... thought about it, but was lazy. Regretting that now, seeing all the comments on QC of these.

[panzermk2]

I would like to see the results of your first thoroughly scrubbed results. Once the chamber is thoroughly cleansed a Q-tip soaked with Card Clean after each range trip will normally keep it clean.